scholarly journals Hexavalent sperm-binding IgG antibody released from vaginal film for development of potent on-demand nonhormonal female contraception

2021 ◽  
Vol 118 (48) ◽  
pp. e2107832118
Author(s):  
Bhawana Shrestha ◽  
Kathleen Vincent ◽  
Alison Schaefer ◽  
Yong Zhu ◽  
Gracie Vargas ◽  
...  

Nonhormonal products for on-demand contraception are a global health technology gap; this unmet need motivated us to pursue the use of sperm-binding monoclonal antibodies to enable effective on-demand contraception. Here, using the cGMP-compliant Nicotiana-expression system, we produced an ultrapotent sperm-binding IgG antibody possessing 6 Fab arms per molecule that bind a well-established contraceptive antigen target, CD52g. We term this hexavalent antibody “Fab-IgG-Fab” (FIF). The Nicotiana-produced FIF had at least 10-fold greater sperm-agglutination potency and kinetics than the parent IgG, while preserving Fc-mediated trapping of individual spermatozoa in mucus. We formulated the Nicotiana-produced FIF into a polyvinyl alcohol–based water-soluble contraceptive film and evaluated its potency in reducing progressively motile sperm in the sheep vagina. Two minutes after vaginal instillation of human semen, no progressively motile sperm were recovered from the vaginas of sheep receiving FIF Film. Our work supports the potential of multivalent contraceptive antibodies to provide safe, effective, on-demand nonhormonal contraception.

2021 ◽  
Author(s):  
Bhawana Shrestha ◽  
Kathleen Vincent ◽  
Alison Schaefer ◽  
Yong Zhu ◽  
Gracie Vargas ◽  
...  

Non-hormonal products for on-demand contraception are a global health technology gap, motivating us to pursue the use of sperm-binding monoclonal antibodies as a strategy to enable safe, effective, desirable, on-demand contraception. Here, using cGMP-compliant Nicotiana-expression system, we produce an ultra-potent sperm-binding IgG antibody possessing 6 Fab arms per molecule that bind a well-established contraceptive antigen target, CD52g. We term this hexavalent antibody Fab-IgG-Fab (FIF) to reflect its molecular orientation. The Nicotiana-produced FIF exhibits at least 10-fold greater sperm agglutination potency and kinetics than the parent IgG, while preserving Fc-mediated trapping of individual spermatozoa in mucus. We formulate the Nicotiana-produced FIF into a polyvinyl alcohol-based water-soluble contraceptive film, and evaluate its potency in reducing progressively motile sperm in the sheep vagina. Two minutes after vaginal instillation of human semen, no progressively motile sperm are recovered from the vaginas of sheep receiving FIF-Film. In contrast, high numbers of progressively motile sperm are recovered from sheep receiving a placebo film control. Our work supports the potential of highly multivalent contraceptive antibodies to provide safe, effective, on-demand non-hormonal contraception.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1110
Author(s):  
Kunal Jhunjhunwala ◽  
Charles W. Dobard ◽  
Sunita Sharma ◽  
Natalia Makarova ◽  
Angela Holder ◽  
...  

Receptive anal intercourse (RAI) contributes significantly to HIV acquisition underscoring the need to develop HIV prevention options for populations engaging in RAI practices. We explored the feasibility of formulating rectal suppositories with potent antiviral drugs for on-demand use. A fixed-dose combination of tenofovir (TFV) and elvitegravir (EVG) (40 mg each) was co-formulated in six different suppository bases (three fat- and three water-soluble). Fat-soluble witepsol H15 and water-soluble polyethylene glycol (PEG) based suppositories demonstrated favorable in vitro release and were advanced to assess in vivo pharmacokinetics following rectal administration in macaques. In vivo drug release profiles were similar for both suppository bases. Median concentrations of TFV and EVG detected in rectal fluids at 2 h were 1- and 2-logs higher than the in vitro IC50, respectively; TFV-diphosphate levels in rectal tissues met or exceeded those associated with high efficacy against rectal simian HIV (SHIV) exposure in macaques. Leveraging on these findings, a PEG-based suppository with a lower dose combination of tenofovir alafenamide (TAF) and EVG (8 mg each) was developed and found to achieve similar rectal drug exposures in macaques. This study establishes the utility of rectal suppositories as a promising on-demand strategy for HIV PrEP and supports their clinical development.


Author(s):  
Yong Zhu ◽  
Jamal Saada ◽  
Shrestha Bhawana ◽  
Sam Lai ◽  
Paula Villarreal ◽  
...  

Abstract High unintended pregnancy rates are partially due to lack of effective nonhormonal contraceptives; development of safe, effective topical vaginal methods will address this need. Preclinical product safety and efficacy assessment requires in vivo testing in appropriate models. The sheep is a good model for the evaluation of vaginally delivered products due to its close similarities to humans. The study objective was to develop an ovine model for efficacy testing of female nonhormonal contraceptives that target human sperm. Fresh human semen was pooled from male volunteers. Nonpregnant female Merino sheep were treated with control or vaginal contraceptive product (IgG antibody with action against sperm or nonoxynol-9 [N9]). Pooled semen was added to the sheep vagina and mixed with product and vaginal secretions. Microscopic assessment of samples was performed immediately and progressive motility (PM) of sperm was compared between treatments. Cytokines CXCL8 and IL1B were assessed in vaginal fluid after instillation of human semen. No adverse reactions or elevations in proinflammatory cytokines occurred in response to human semen. N9 produced signs of acute cellular toxicity while there were no cellular changes after IgG treatment. N9 and IgG had dose-related effects with the highest dose achieving complete sperm immobilization (no sperm with PM). Surrogate post-coital testing of vaginally administered contraceptives that target human semen was developed in an ovine model established for vaginal product preclinical testing. This expanded model can aid the development of much needed nonhormonal topical vaginal contraceptives, providing opportunities for rapid iterative drug development prior to costly, time-intensive human testing.


1996 ◽  
Vol 319 (2) ◽  
pp. 411-420 ◽  
Author(s):  
Torben ØSTERLUND ◽  
Birgitta DANIELSSON ◽  
Eva DEGERMAN ◽  
Juan Antonio CONTRERAS ◽  
Gudrun EDGREN ◽  
...  

Hormone-sensitive lipase (HSL) plays a key role in lipid metabolism and overall energy homoeostasis, by controlling the release of fatty acids from stored triglycerides in adipose tissue. Lipases and esterases form a protein superfamily with a common structural fold, called the α/β-hydrolase fold, and a catalytic triad of serine, aspartic or glutamic acid and histidine. Previous alignments between HSL and lipase 2 of Moraxella TA144 have been extended to cover a much larger part of the HSL sequence. From these extended alignments, possible sites for the catalytic triad and α/β-hydrolase fold are suggested. Furthermore, it is proposed that HSL contains a structural domain with catalytic capacity and a regulatory module attached, as well as a structural N-terminal domain unique to this enzyme. In order to test the proposed domain structure, rat HSL was overexpressed and purified to homogeneity using a baculovirus/insect-cell expression system. The purification, resulting in > 99% purity, involved detergent solubilization followed by anion-exchange chromatography and hydrophobic-interaction chromatography. The purified recombinant enzyme was identical to rat adipose-tissue HSL with regard to specific activity, substrate specificity and ability to serve as a substrate for cAMP-dependent protein kinase. The recombinant HSL was subjected to denaturation by guanidine hydrochloride and limited proteolysis. These treatments resulted in more extensive loss of activity against phospholipid-stabilized lipid substrates than against water-soluble substrates, suggesting that the hydrolytic activity can be separated from recognition of lipid substrates. These data support the concept that HSL has at least two major domains.


2020 ◽  
Vol 8 (29) ◽  
pp. 10047-10059 ◽  
Author(s):  
Do-Gwan Kim ◽  
Dowon Ahn ◽  
Kang-Han Kim ◽  
Yong-Cheol Jeong

Herein, we report a wearable strain sensor, composed of a water-soluble metal electrode and a pH-sensitive encapsulation layer, with conforming flexibility and super wear-resistance.


2015 ◽  
Vol 19 (01-03) ◽  
pp. 492-499 ◽  
Author(s):  
Scott D. Hicks ◽  
Silei Xiong ◽  
Curt J. Bougher ◽  
Grigori A. Medvedev ◽  
James Caruthers ◽  
...  

A water-soluble manganese porphyrin complex was examined for the catalytic formation of chlorine dioxide from chlorite under ambient temperature at pH 5.00 and 6.90. Quantitative kinetic modeling allowed for the deduction of a mechanism that accounts for all experimental observations. Catalysis is initiated via an OAT (Oxygen Atom Transfer) reaction resulting in formation of a putative manganese(V) oxo species, which undergoes ET (Electron Transfer) with chlorite to form chlorine dioxide. As chlorine dioxide accumulates in solution, chlorite consumption slows down and ClO 2 reaches a maximum as the system reaches equilibrium. In phosphate buffer at pH 6.90, manganese(IV) oxo accumulates and its reaction with ClO 2 gives ClO 3-. However, at pH 5.00 acetate buffer proton coupled electron transfer (PCET) from chlorite to manganese(IV) oxo is fast and irreversible leading to chlorate formation only via the putative manganese(V) oxo species. These differences underscore how PCET rates affect reaction pathways and mechanism. The ClO 2 product can be collected from the aqueous reaction mixture via purging with an inert gas, allowing for the preparation of chlorine dioxide on-demand.


2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Laili Che Rose ◽  
Joseph C. Bear ◽  
Paul D. McNaughter ◽  
Paul Southern ◽  
R. Ben Piggott ◽  
...  

2016 ◽  
Vol 114 (3) ◽  
pp. 451-456 ◽  
Author(s):  
Benedetto Marelli ◽  
Nereus Patel ◽  
Thomas Duggan ◽  
Giovanni Perotto ◽  
Elijah Shirman ◽  
...  

We report simple, water-based fabrication methods based on protein self-assembly to generate 3D silk fibroin bulk materials that can be easily hybridized with water-soluble molecules to obtain multiple solid formats with predesigned functions. Controlling self-assembly leads to robust, machinable formats that exhibit thermoplastic behavior consenting material reshaping at the nanoscale, microscale, and macroscale. We illustrate the versatility of the approach by realizing demonstrator devices where large silk monoliths can be generated, polished, and reshaped into functional mechanical components that can be nanopatterned, embed optical function, heated on demand in response to infrared light, or can visualize mechanical failure through colorimetric chemistries embedded in the assembled (bulk) protein matrix. Finally, we show an enzyme-loaded solid mechanical part, illustrating the ability to incorporate biological function within the bulk material with possible utility for sustained release in robust, programmably shapeable mechanical formats.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e16089-e16089 ◽  
Author(s):  
Jeffery Shyh-Jye Lin ◽  
Nir Kleinmann ◽  
Gregory J Wirth ◽  
Surena F. Matin ◽  
Gil Mayer ◽  
...  

e16089 Background: There is a large unmet need for novel drug delivery systems and effective therapy for UTUC, especially for patients with CKD and anatomic solitary kidneys. A temperature sensitive water-soluble gel formulation of Mitomycin C (MMC) demonstrated increased drug delivery time (4 to 6 hrs) and safety in the pelvicalyceal system of swine and human bladders. We report the efficacy and safety of gel+MMC as primary treatment (tx) of UTUC on a compassionate use basis. Methods: Compassionate use approval was obtained on an individual patient basis from the respective regulatory authorities and IRBs. 22 patients were approved for tx to date from 14 institutions in 4 countries. Tx included 6 weekly instillations instilled via ureteral catheter or percutaneous nephrostomy. Gel volume ranged from 5-20cc and MMC concentration was 2-6 mg/cc. Adverse events were recorded throughout treatment. Ureteroscopy was performed 2-6 weeks following tx completion for response determination. Results: Median age of the cohort was 75 yrs, with 15 males. 18 patients (pts) had low-grade (LG) tumor, 2 high-grade (HG), and 2 indeterminate grade. 16 (73%) completed treatment - 9 pts had a complete response, CR (41%; 59% of those who completed tx), 5 pts had a partial response, PR (23%; 31%), and 2 pts had no response, NR (9.1%, 12.5%). 4 patients could not complete tx due to adverse events (pyelonephritis, acute renal failure, pancytopenia, and unstable cardiac condition), 1 patient was diagnosed with a non-urothelial cancer during treatment, and 1 patient died prior to the third instillation due to suspected pulmonary embolus, determined to be unrelated to treatment with MitoGel. A total of 77 adverse events were recorded with 6 events related to MitoGel and serious (requiring intervention), and 21 events related to treatment and not serious. CR (9) and PR (5) were observed in 14 of 15 evaluable patients completing treatment for LG tumors. Conclusions: This compassionate use program of a thermosensitive gel+MMC for chemoablation of UTUC demonstrates proof of concept for treatment of low-grade tumors. A single arm Phase III multi-center registration trial to treat patients with low-grade renal pelvis tumors has been activated.


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